In the field of display, flat-panel displays with high PPI (Pixels per inch) values have become a key competition for manufacturers. However, in the case that a panel has a high PPI value, a number of issues in, for example, power consumption and light transmission will occur. As a result, it has become a technical problem to increase a saturation current and ensure a certain charging rate by increasing a channel width in the case of a reduced opaque area for a thin film transistor (TFT) array substrate.
For the conventional TFT array substrate, its channel and gate electrode layer are each of a flat structure as a film, so it is impossible to fully and reasonably utilize a spatial volume to increase the saturation current.